Complementary usage of Rhodiola crenulata (L.) in chronic obstructive pulmonary disease patients: the effects on cytokines and T cells.

Although chronic obstructive pulmonary disease (COPD) is an inflammatory disease predominantly involving T cells, no study of Rhodiola as an immunomodulator in COPD patients has been reported. In this study, COPD patients took Rhodiola crenulata 500 mg (n = 38) or placebo (starch/phosphate buffered saline) (n = 19) daily for 12 weeks and were compared with untreated, age-matched, and sex-matched non-COPD control subjects. Our results showed that serum levels of IL-2, IL-10, and IFN-γ in COPD patients before treatment are significantly higher than levels in non-COPD controls (p < 0.05). A significant decrease in IFN-γ was seen in the Rhodiola treatment group (p < 0.05) but not in the placebo group (p > 0.05). The results suggested that Rhodiola treatment had beneficial antiinflammation effects, lower COPD assessment test score and decreased high-sensitivity C-reactive protein, on COPD patients (p < 0.05). The effects of Rhodiola treatment on COPD patients were shown to decrease the IFN-γ concentration and CD8(+) count but increase the expressions of CD4(+) CD25(+) FOXP3(+) and CD4(+) CD25(+) CD45(+) FOXP3(+) in the blood significantly (p < 0.05). This is the first trial using Rhodiola as a complementary therapy for COPD patients. T cells play an important role in the pathogenesis of COPD through the increased expression of CD8(+) T cells and IFN-γ and may be a viable target for potential therapy.